Measurement of transmittance and permittivity of dielectric materials using dispersive Fourier transform spectroscopy

摘要

Transmittance and permittivity of several dielectric materials such as plexiglas, acrylic, and polypropylene were measured using dispersive Fourier transform spectroscopy (DFTS). The measured results showed that the transmittance of plexiglas and acrylic specimens decreases with the increase of frequency in the range of 50-380 GHz. Accurate spectra of complex permittivity and loss tangent of these specimens in this frequency range are also given. Very good agreement was seen in the overlapped frequency range between the measured data and the published data, measured using other techniques such as the W-band spectrometer with backward wave oscillator and the free-space measurement. This technique can be used for measurements of various dielectric materials, provided that fiat specimens are available.